I love this experimental discovery and its implications for electrodynamics. All fundamental particles are cousins of the quantum units of electromagnetic energy (photons), but none more so than the ubiquitous electron. Very cool work by Professor Anne Sickles of my alma mater, The University of Illinois, via the ATLAS experiment at CERN via the LHC.
https://www.symmetrymagazine.org/article/a-collision-of-light